Along the northern and western sides of the site, a low bank of earth and stone, roughly 1.4 metres wide, runs alongside an external fosse, a shallow ditch, approximately 1.5 metres across. Together, these features suggest that the graveyard does not mark the beginning of this site's sacred use, but something closer to its continuation.

The bank and fosse are read by archaeologists as possibly the remnant of an earlier ecclesiastical enclosure, the kind of boundary that would have defined an early Irish monastic or church site, demarcating sacred ground from the surrounding landscape. Such enclosures, often circular or curvilinear in plan, are a characteristic feature of early medieval religious settlements in Ireland, and their earthworks frequently survived long after the communities that made them had dissolved, absorbed quietly into later land use. At Knockatemple, the name itself, derived from the Irish for "hill of the church", points to a religious association that predates any surviving structure.